A Supplementary Collections Module for [Ceylon](http://ceylon-lang.org). This module was inspired by and adapted from [Google Guava](https://github.com/google/guava) under the Apache License Version 2.0. Currently implemented types are: * [[ArrayListMultimap]]: a mutable `Collection<Key->Item>` and `Correspondence` from `Key` to `MutableList<Item>` that supports deterministic iteration order for both keys and items. * [[LinkedListMultimap]]: a mutable `Collection<Key->Item>` and ...